fix(deps): update dependency google-gax to v4.3.9

[renovate-bot]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
google-gax (source)	4.3.8 -> 4.3.9

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Release Notes

googleapis/gax-nodejs (google-gax)

### [`v4.3.9`](https://togithub.com/googleapis/gax-nodejs/blob/HEAD/gax/CHANGELOG.md#439-2024-08-06) [Compare Source](https://togithub.com/googleapis/gax-nodejs/compare/google-gax-v4.3.8...google-gax-v4.3.9) ##### Bug Fixes - reduce duplicate code in streaming retries and add a test ([#​1636](https://togithub.com/googleapis/gax-nodejs/issues/1636)) ([83b52e1](https://togithub.com/googleapis/gax-nodejs/commit/83b52e14ba3bb1e9f0e079ea53e47ec32b4cfd45)) - test application cleanup ([#​1639](https://togithub.com/googleapis/gax-nodejs/issues/1639)) ([76ac496](https://togithub.com/googleapis/gax-nodejs/commit/76ac496fe42f1176df733d0adcc755bd4e773b10))

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